738
FXUS62 KCHS 101109
AFDCHS
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
709 AM EDT FRI JUL 10 2026
WHAT HAS CHANGED
THE AVIATION SECTION WAS UPDATED FOR THE 12Z TAFS.
KEY MESSAGES
- 1) HOT AND HUMID CONDITIONS ACROSS COASTAL SOUTH CAROLINA AND GEORGIA
TODAY, POSSIBLY AGAIN ON SATURDAY. SCATTERED THUNDERSTORMS
EXPECTED TO DEVELOP NEAR THE SEA BREEZE LATE THIS AFTERNOON
INTO THIS EVENING. SOME OF THESE STORMS MAY BECOME STRONG TO
SEVERE, WITH LOCALIZED DAMAGING WIND GUSTS.
- 2) TYPICAL SUMMERTIME AFTERNOON AND EVENING THUNDERSTORMS
THIS WEEKEND, WITH INCREASING RAIN CHANCES SUNDAY THROUGH
TUESDAY.
-3) COASTAL FLOODING IS POSSIBLE WITH THE EVENING HIGH TIDE FROM
SUNDAY THROUGH WEDNESDAY.
DISCUSSION
KEY MESSAGE 1: HOT AND HUMID CONDITIONS ACROSS COASTAL SOUTH
CAROLINA AND GEORGIA TODAY, POSSIBLY AGAIN ON SATURDAY. SCATTERED
THUNDERSTORMS EXPECTED TO DEVELOP NEAR THE SEA BREEZE LATE THIS
AFTERNOON INTO THIS EVENING. SOME OF THESE STORMS MAY BECOME STRONG
TO SEVERE, WITH LOCALIZED DAMAGING WIND GUSTS.
TODAY, A SFC TROUGH IS FORECAST TO REMAIN OVER THE CENTRAL CAROLINAS
THIS AFTERNOON, SUPPORTING WSW WINDS ACROSS SE GA AND SC. DUE TO THE
WSW WINDS, THE SEA BREEZE MAY REMAIN PINNED ALONG THE COAST, THEN
PUSHING INLAND LATE THIS AFTERNOON INTO EARLY THIS EVENING. AS THE
SEA BREEZE PUSHES INLAND, DEWPOINTS SHOULD RISE INTO THE UPPER 70S,
WITH SOME VALUES AROUND 80. TEMPERATURES ALONG AND AHEAD OF THE SEA
BREEZE SHOULD PEAK IN THE UPPER 90S BY MID AFTERNOON. THE HOT
TEMPERATURES COMBINED WITH THE ELEVATED DEWPOINTS SHOULD RESULT
IN A CORRIDOR OF HEAT INDEX VALUES BETWEEN 106 TO 113 DEGREES.
AN EXTREME HEAT WARNING WILL REMAIN IN EFFECT FOR CHARLESTON AND
TIDAL BERKELEY COUNTIES FROM 11 AM TO 7 PM. A HEAT ADVISORY
WILL HIGHLIGHT THE AREA FROM DORCHESTER COUNTY SOUTH ACROSS THE
COAST OF SC AND GA. SIMILAR HEAT INDEX VALUES ARE POSSIBLE OVER
THE SAME AREAS ON SATURDAY.
THE HOT AND HUMID CONDITIONS WILL LIKELY YIELD MODERATE INSTABILITY
ACROSS THE COASTAL COUNTIES OF SE GA/SC. RECENT RUNS OF THE HRRR,
RRFS, AND HREF INDICATE THAT SCATTERED TO ISOLATED
THUNDERSTORMS DEVELOPING ALONG AND NEAR THE SEA BREEZE LATE THIS
AFTERNOON AND EVENING. FORECAST SOUNDINGS INDICATE THAT ONCE
STORMS DEVELOP, STEERING FLOW SHOULD CAUSE THE STORMS TO TRACK
EAST BETWEEN 15 TO 20 MPH. GIVEN SBCAPE BETWEEN 2500-3500 J/KG
WITH POCKETS OF 4000 J/KG AND DCAPE AROUND 1000 J/KG, THE
ENVIRONMENT MAY SUPPORT SOME DAMAGING WET MICROBURSTS. MACHINE
LEARNING PRODUCTS INDICATE THAT THE GREATEST CHANCE FOR STRONG
TO SEVERE THUNDERSTORMS WILL REMAIN ALONG AND EAST OF THE I-95
CORRIDOR, FAVORING AREAS ALONG AND NORTH OF THE SAVANNAH RIVER.
SPC GENERALLY HIGHLIGHTS THE SAME AREA WITH MARGINAL RISK FOR
DAMAGING WIND GUSTS. THUNDERSTORMS COVERAGE SHOULD STEADILY
DECREASE BY MID EVENING, WITH STORMS PUSHING OFFSHORE.
KEY MESSAGE 2: TYPICAL SUMMERTIME AFTERNOON AND EVENING
THUNDERSTORMS THIS WEEKEND, WITH INCREASING RAIN CHANCES SUNDAY
THROUGH TUESDAY.
SATURDAY: AMIDST THE CONTINUING HOT AND HUMID CONDITIONS, RAINFALL
CHANCES WILL REMAIN ISOLATED TO SCATTERED. H500 HEIGHTS REMAIN QUITE
CONSISTENT, WITH THE DIURNAL SEA-BREEZE EXPECTED TO BE THE MAIN
TRIGGER FOR AFTERNOON CONVECTION. SIMILAR TO FRIDAY, EXPECT 1500-
2500 J/KG OF CAPE TO BUILD INTO THE AFTERNOON HOURS, WITH SHEAR
GENERALLY REMAINING UNIMPRESSIVE AT NEAR 20 KNOTS. WITH
PRECIPITABLE WATER VALUES REMAINING IN THE 1.5-2 INCH RANGE AND
DCAPE VALUES NEAR 1000 J/KG, STRONG DAMAGING WINDS REMAIN THE
PRIMARY RISK.
SUNDAY - TUESDAY: WHILE THE ATLANTIC SURFACE HIGH PRESSURE
CONTINUES, WEAK H500 TROUGHING TO OUR NORTH WILL BRING A WEAK
SURFACE LOW PRESSURE OFF THE VIRGINIA/NORTH CAROLINA COAST AND
INTO THE ATLANTIC ON SUNDAY. A WEAK COLD FRONT ASSOCIATED WITH
THE SURFACE LOW WILL SLOWLY SAG DOWN INTO THE REGION, BRINGING
INCREASED CHANCES FOR SHOWERS AND THUNDERSTORMS TO THE REGION.
WHILE AGREEMENT AMONGST THE MODELS IS NOT HIGH, A FEW MODELS
CONTINUE TO DEPICT A WEAK SURFACE LOW PRESSURE DEVELOPING ALONG
THE COLD FRONT, MOVING ACROSS THE AREA SUNDAY NIGHT BEFORE
PUSHING OFFSHORE ON MONDAY. DESPITE SLIGHTLY COOLER
TEMPERATURES, WITH HIGHS EXPECTED TO FALL INTO THE LOWER/MID
90S, 1500-2000 J/KG OF CAPE WILL CONTINUE ISOLATED CHANCES FOR
STRONG-SEVERE THUNDERSTORMS. WITH ASTRONOMICAL HIGH TIDE OF 6.44
FT MLLW OCCURRING SHORTLY AFTER 7 PM, ANY THUNDERSTORM ACTIVITY
NEAR THE CHARLESTON PENINSULA WILL INCREASE CHANCES FOR
IMPACTFUL FLOODING.
COOLER AIR CONTINUES TO FILTER DOWN INTO THE REGION AS A SURFACE
HIGH PRESSURE MOVING TOWARDS/ACROSS THE APPALACHIANS, WITH THE FRONT
REMAINING ACROSS/SOUTH OF THE REGION CONTINUING PERIODIC CHANCES FOR
RAINFALL ON MONDAY AND TUESDAY. THIS WILL BRING TEMPERATURES DOWN
INTO THE MID/UPPER 80S ON BOTH DAYS. H500 HEIGHTS BEGIN TO RISE
AGAIN ON WEDNESDAY AS THE RIDGE STRENGTHENS, WITH TEMPERATURES
RISING BACK UP INTO THE LOWER 90S.
KEY MESSAGE 3: COASTAL FLOODING IS POSSIBLE WITH THE EVENING HIGH
TIDE FROM SUNDAY THROUGH WEDNESDAY.
ASTRONOMICAL FORCES ON TIDES WILL INCREASE EARLY NEXT WEEK, WITH A
LUNAR PERIGEE ON MONDAY AND A NEW MOON ON TUESDAY. MINOR COASTAL
FLOODING IS POSSIBLE ACROSS CHARLESTON AND COASTAL COLLETON COUNTIES
SUNDAY EVENING. COASTAL FLOODING MAY INCREASE MONDAY THROUGH
WEDNESDAY WITH RISING ASTRO TIDES AND ONSHORE WINDS. IN ADDITION,
RAINFALL MAY OVERLAP WITH THE EVENING HIGH TIDE CYCLES, SEE KEY
MESSAGE 2 FOR ADDITIONAL DETAILS.
AVIATION /12Z FRIDAY THROUGH TUESDAY/
12Z TAFS: TERMINALS WILL REMAIN VFR WITH LIGHT SOUTHWEST WINDS
THIS MORNING. ISOLATED TO SCATTERED THUNDERSTORMS ARE FORECAST
TO DEVELOP NEAR THE SEA BREEZE THIS AFTERNOON, EXPECTED TO
DEVELOP NEAR OR OVER THE TERMINALS BETWEEN 20-24Z, HIGHLIGHTED
WITH TEMPOS AT KCHS AND KJZI AND PROB30 UNTIL 2Z AT KSAV. AS THE
SEA BREEZE DEVELOPS, WINDS WILL DEVELOP GUSTS BETWEEN 20 TO 25
KTS, ESPECIALLY AT KCHS AND KJZI. CONVECTION AND WIND GUSTS
SHOULD PUSH OFFSHORE THIS EVENING.
EXTENDED AVIATION OUTLOOK: THERE WILL BE A LOW END RISK OF
THUNDERSTORM IMPACTS SATURDAY AFTERNOON AND EVENING. SHOWER AND
THUNDERSTORM COVERAGE, ALONG WITH RISKS OF ASSOCIATED RESTRICTIONS,
MAY INCREASE SUNDAY THROUGH TUESDAY.
MARINE
TODAY INTO TONIGHT: THE SEA BREEZE WILL LIKELY TRIGGER SCATTERED
THUNDERSTORM ACROSS THE COAST LATE THIS AFTERNOON. THESE STORMS ARE
FORECAST TO PUSH OVER THE ATLANTIC WATERS THROUGH EARLY THIS
EVENING. SOME OF THE STORMS MAY YIELD GUSTY WINDS, REQUIRING SPECIAL
MARINE WARNINGS.
SURGES IN THE WAKE OF THE SEA BREEZE MAY RESULT IN SOUTHWEST WINDS
TO INCREASE DURING THIS AFTERNOON AND CONTINUE INTO TONIGHT.
WIND GUSTS MAY PEAK AROUND 25 KTS, POSSIBLY REQUIRING SMALL
CRAFT ADVISORIES. THE SHORT DURATION OF THE ELEVATED WINDS
SHOULD KEEP WAVE HEIGHTS BETWEEN 3 TO 4 FT. WINDS SHOULD START
TO DIMINISH AFTER MIDNIGHT.
SATURDAY INTO WEDNESDAY: ATLANTIC SURFACE HIGH PRESSURE WILL
CONTINUE TO SUPPORT SOUTH-SOUTHWEST WINDS BETWEEN 15 TO 20 KNOTS,
WITH OCCASIONAL GUSTS INTO THE LOWER-MID 20S ON SATURDAY. WHILE WAVE
HEIGHTS ARE FORECAST TO FAVOR 3 TO 4 FT, A SHORT-LIVED SMALL CRAFT
ADVISORY CANNOT BE RULED OUT, ESPECIALLY ALONG THE NEARSHORE WATERS
FROM SOUTH SANTEE TO EDISTO BEACH. SUNDAY INTO MONDAY IS EXPECTED TO
SEE A WEAK COLD FRONT SAG INTO THE REGION FROM THE NORTH, BRINGING
WEAKER WESTERLY WINDS ON SUNDAY BECOMING NORTH-NORTHEASTERLY MONDAY
MORNING. SURFACE FLOW LOOKS TO BECOME VARIABLE LATER ON MONDAY, WITH
A SURFACE HIGH PRESSURE MOVING IN FROM THE NORTH ON TUESDAY
SWITCHING WINDS AROUND TO BECOME OUT OF THE NORTHEAST.
RIP CURRENTS: A MODERATE RISK FOR RIP CURRENTS WILL REMAIN ALONG THE
SC/GA COAST TODAY AND SATURDAY. CONDITIONS WILL FEATURE 2-3 FT
SWELL WITH WAVE PERIODS UP TO 9 SECONDS. IN ADDITION, SSW WINDS
WILL LIKELY GENERATE A MODERATE LONGSHORE CURRENT, POSSIBLY
SUPPORTING RIP CURRENTS NEAR PIERS AND JETTIES.
CLIMATE
RECORD HIGH TEMPERATURES:
JULY 10:
KCHS: 100/1986
KCXM: 99/1986
KSAV: 102/1879
JULY 11:
KCHS: 102/1986
KCXM: 100/2001
KSAV: 103/1980
RECORD HIGH MINIMUM TEMPERATURES:
JULY 10:
KCHS: 81/1986
KCXM: 82/1986
JULY 11:
KCHS: 80/2016
KCXM: 82/2016
JULY 12:
KCHS: 79/2020
CHS WATCHES/WARNINGS/ADVISORIES
GA...HEAT ADVISORY FROM 11 AM THIS MORNING TO 7 PM EDT THIS EVENING
FOR GAZ217>219-239-241.
SC...HEAT ADVISORY FROM 11 AM THIS MORNING TO 7 PM EDT THIS EVENING
FOR SCZ044-045-148-149-151.
EXTREME HEAT WARNING FROM 11 AM THIS MORNING TO 7 PM EDT THIS
EVENING FOR SCZ150-152.
MARINE...NONE.
APT/NED
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